Chapter 28 Exam 2 Flashcards
Human progress has always depended on expanding our use of plants for
Food
Fuel
Clothing
one of the most important agricultural products in the world today.
Coffee
Ground coffee is made from the ____ belonging to several species in the genus Coffea
seeds of plants
Coffee was discovered in Ethiopia during the
1200s
Coffee was discovered in __ during the 1200s.
Ethiopia
By the ____, coffee plants imported to the Americas were an important crop.
1700s
naturally produced by the coffee plant as a
self-defense against herbivores
Coffee does what
stimulates the nervous system
Plants are vital to the well-being of not just humans but the entire
biosphere
the flowering plants—make up more than 90% of the plant kingdom.
Angiosperms
Angiosperms make up more than __% of the plant kingdom.
90%
biologists who study plants
botanists
• On the basis of several structural differences, botanists (biologists who study plants) classify most angiosperms into two groups:
- Monocots
2. Eudicots
The names of the groups refer to embryonic structures called
cotyledons,
or seed leaves
the first leaves to emerge from a growing seedling.
cotyledons,
or seed leaves
Monocot embryo has
One seed leaf
Eudicot embryo has
Two seed leaves
many food crops (such as nearly all of our fruits and vegetables)
Eudicots
The majority of ornamental plants are
Eudicots
Most shrubs and trees (except for the gymnosperms)
Eudicots
consists of several types of tissues that together carry out a particular function. This includes roots, stems, leaves
Organs
an organ that
anchors a plant in the soil, absorbs and transports minerals and water, and stores food
Root
All of a plant’s roots make up its
root system
are tiny projections near the root tips
Root hairs
greatly increase the root surface area, providing an extensive outer layer for absorption of water and minerals.
Root hairs
found in carrots, turnips, sugar beets, and sweet potatoes
Large taproots
store food in the form of carbohydrates such as starch or sucrose.
Large taproots
______of a plant is made up of stems, leaves, flowers
shoot system
grow above the ground and support the flowers and leaves.
Stems
Has nodes and internodes
Stem
the points at which leaves are attached
Nodes
the portions of the stem between nodes.
Internodes
In many plants, the terminal bud produces hormones that inhibit growth of the axillary buds, a phenomenon called
apical dominance
Removing the terminal bud by pruning a fruit tree or “pinching back” a houseplant will make the plant
Bushier
has rhizomes ending in enlarged structures called tubers, where food is stored in the form of starch.
Potato
A potato plant has
Rhizomes
where food is stored in the form of starch.
Tubers
The ___ of a potato are axillary buds, which can grow into new plants, allowing potatoes to be easily propagated.
“eyes”
The “eyes” of a potato are
axillary buds
can grow into new plants, allowing potatoes to be easily propagated.
Axillary buds
the primary sites of photosynthesis in most plants
Leaves
This has a flattened blade and a stalk, or petiole
Leaf
joins the leaf to the stem
petiole
are groups of cells that together perform a specialized function.
Tissues
This tissue conveys water and dissolved minerals upward from the roots to the stems and leaves
Xylem
transports sugars from leaves or
storage tissues to other parts of the plant.
Phloem
consists of one or more tissues organized into a functional unit within a plant.
Tissue system
Each plant organ—is made up of three tissue systems:
the dermal,
vascular,
and ground tissue systems.
Each tissue system is continuous throughout the entire plant body, but the systems are ___
arranged differently in leaves, stems, and roots.
forms an outer protective covering
Dermal tissue system
forms a first line of defense against physical damage and infectious organisms
Dermal tissue system
On leaves and on most stems, dermal cells secrete a waxy coating
cuticle
which helps prevent water loss
the cuticle
provides support and long-distance transport
throughout the plant and includes xylem and phloem
Vascular tissue system
accounts for most of the bulk of a plant and has diverse functions, including photosynthesis, storage, support
The ground tissue system
- photosynthesis,
- storage,
- support.
Ground tissue system
where cells store food and take up water and minerals.
cortex
The innermost layer of cortex is the____, a thin cylinder one cell thick.
endodermis
a selective barrier that regulates the passage of substances between the cortex and the vascular tissue
endodermis
The epidermis contains __, tiny pores between two specialized _____,
stomata;
guard cells
which regulate the opening and closing of the stomata, allowing gas exchange between the surrounding air and photosynthetic cells inside the leaf
Guard cell
The main site of photosynthesis is the____, which is the ground tissue of a leaf.
mesophyll
The leaf’s vascular tissue system is made up of a ___
network of veins
The epidermis (the outer layer of the dermal system) is a single layer of tightly packed cells covering the entire root. ______from the soil enter the plant through these cells.
Water and minerals
cells that radiate from the center
Xylem
cells filling in the wedges between the spokes
Phloem
contains stomata, tiny pores between two specialized guard cells
Epidermis
Most plant cells have three unique structures
Chloroplasts
Central vacuole
Cell wall
are the sites of photosynthesis
Chloroplasts
A large _____ containing fluid helps
maintain the cell’s firmness
central vacuole
surrounds the plasma membrane and consists largely of the carbohydrate cellulose.
cell wall
the most abundant type of cell in most plants
Parenchyma cells
